Cell for electrodeposition of metals



Oct. 30, 1928.

R. D; PIKE ET AL CELL FOR ELECTRODEPOSITION OF METALS s Sheets-Sheet 1 Filed Sept. 23, 1925 5 a R H s mr R VkumVO T flw r 02 A a r: RPM Y B Oct 30, 1928. 1,689,597

R. D. PIKE ET AL CELL FOR ELECTRODEPOSITION OF METALS Filed Sept. 25, 1925 3 Sheets-Sheet 2 i 5 1 5 1 5 i i l 1 1 a IN V EN TORS. Robert D. Pike. Geo H. West,

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Oct. 30, 1.928. 1,689,597

1 R. D. PIKE ET AL CELL FOR ELECTRODEPOSITION OF METALS Filed Sept. 25, 1925 5 Sheets-Sheet 5 IIIIIIIIIIA CD a;

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Patented Oct. 30,192

UNITED sTA'rEs 1,689,597 PATENT OFFICE.

ROBERT D. PIKE, or PIEDMONT, GEORGE WES -or BERKELEY, am) BENJAMIN PLUMMER LITTLE, 0E OAKLAND, CAL FORNIA; SAID wEsT am) LITTLE ASSIGNORS TO SAID BDBEBT D. BIKE.

oELL Iron Emc'rnonErosnIoN 0E METALS.

Application filed September 23, 1925. Serial No. 58,010.

. Our present invention relates to a cell for electro-deposition of iron, and has for its object to providean apparatus suitable for use in carrying out the method invention disclosed in the co-pending application by Robert D. Pike for patent filed on this same date for method for electro-deposition of iron, Serial Number 58,009. The cell covered by this application is particularly adapted for electro-deposition of iron, but is also applicable to the deposition of other metals such as zinc, in which hydrogenplays an adverse role in the deposition,

In and by our invention we overcome, in a great measure, the bad effect of hydrogen on the deposited metal. This invention is particularly adapted to deposition of iron'when co-deposition of hydrogen presents great difficulties.- The rotating cathodes are 1n turnsubjected to deposition and the depolarlzing action of atmospheric oxygen. The reaction products are removed from the face of the deposit substantially as formed. Our 1nvention also includes novel methods of circul'ating the anolyte and maintaining a constant liquor level in the anolyte compartment, as well as withdrawing an accurately measured and controlled amount of anolyte. Fig. 1 is an end elevation of the assembled cell; I

Fig. 2 is a half plan view with cover removed and anodes removed to clearly show the diaphragms;

' Fig. 3 is a half plan view with cover removed, showing anodes in place;

Fig. 4 is a half section on line A-A, Fig. 3, with cover and wipers removed;

Fig. 5 is a half section on line B-B, Fig. 2, with cover and wipers removed;

Fig. 6 is an elevation detail showing a cathode with cover .and wipers in place;

Fig. 7 is a section on line C.C, Fig. 6; Fig. 8 is a detail of the wiper;

Fig. 9 is a section of one of the dia phragms;

Fig. 10 is an elevation of one of the diaphragms.

body containing the semi-circular bowl or tank 2, in which are partitioned off the f anode and cathode compartments 3 and 4,

respectively, by means of the diaphragms 5. The cell body contains integrally the anolyte channel 6- connected with each anode compartment by passages 8. Channel '6 extends into channel 10. A valveless plunger pump .12 takes anolyte from this channel 10 and pumps it out of the cell through passage 16 v and orifice 17. A valveless plunger pump 11 takes anolyte from channel 10, and pumps it through passage 15 into heater chamber 19. In this chamber are immersed heater tubes 20, to which steam is admitted through connection 21, and from which condensate drains through connection 22. The heating tubes are preferably of heavy Pyrex glass consisting of an lnner tube (not shown) which extends to near the bottom and through which the steam is admitted. The condensate is blown upwardly in the annular channel between the central tube and outer tube and escapes through the drain 22. The use of this heater may be omitted in certain cases. From the heater the anolyte goes'to channel 7 and returns to the anode compartments, in circulation, through the passages '9- The valveless pumps 11 and 12 are atsuitable electrical connection with the shaft. Rubber sleeves 28 are placed outside of the copper sleeves for preventing corrosion. The entire assembly of discs and sleeves is'held in place against shoulder 29, integral with shaft 23, by nut 30, which engages threads .onthe shaft. In practice the discs are usually from 4m 5 feet in diameter, and are usually rotated atl to 2 R. P. M;

The incomingelectrolyte is admitted into channel 31 through passage 31', and flows into channel 32 through passages 32'. The

amount withdrawn for circulation flows out through weir 33, at which point the general level, of liquor in the cell is maintained.

The pump 12 withdraws a constant volume of anolyte, and as the level in the oathode compartment is maintained substantially constant b weir 33, it follows that the liquor level in t e anode compartment will depend to; a considerable extent upon the porosity of the diaphragms. This latter factor, furthermore, cannot be expected to remain constant, because, as operation of the cell continues, reaction products become deposited in the diaphragm, which reduce its porosity. In iron deposition the liquor flows from the cathode compartment through the diaphragm into the anode compartment, and the level in the latter should be about one-quarter of an inch lower than in the for mer. But, althoug this level may be properly adjusted at the eginning of the operation, it will not stay so adjusted. To over come this difliculty a one-way valve 34 is provided between catholyte channel 31 and anolyte channel 10, which valve opens automaticallyor otherwise and allows c'atholyte to flow into the anolyte when the levelof the latter becomes lower than a certain predetermined point. Valve 34 may be of any suitable construction.

The described arrangement for circulating and controlling the level of the anolyte liquor insures a constant supply of anolyte of unvarying composition to each anode compartment, and this insures operation of the cell at uniform voltage and with uniform depolarizing effect at the anode. This also insures that there will be no chlorine losses when the electrolyte is ferrous chloride in iron deposition. i

The commutator 31 provides electricalconnection by-suitable means (not shown) wit-h the negative terminal of a D. O. generator.

Anodes 35, of suitable material, are suspended in the anode compartment from bars the cross bars 39, from w 36, which in turn rest on the anode bus bars 37 and 37 which are connected b suitable means (not shown) with the positive termif .nal of the D. C.- generator.

It will be understood that in producing iron from an electrolyte of ferrous chloride, the electro-chemical reaction in the cathode compartment is the deposition of iron and ydrogen on the cathode; and in the anode compartment, the so-called depolarizing react1on whereby chlorine unites with ferrous chloride to make ferric chloride. v

The cell is preferably covered with a hood 38, which is also preferabl furnished with controllable top vents and side vents, not shown, for observation or for controlling the passage of outside air through the-hood.

he hood 38 convenientlly; serves to' su port' ich depend oosely the wiper arms 40, which are held loosely and rotatably on the bars 39 by the clips 41. To the lower end of the arms are secured the wipers 42, which are preferably of moderately hard rubber composition containing some powdered carborundum.

As arranged, the weight of the wiper arm and wiper causes the wipers 42 to press gently'against the face of the revolving cathode, the entire face of which is wiped as the disc rotates.

The diaphragm5is preferably made of a rubber-covered steel form 43, which conforms to the semi-circular shape of the bowl of the cell and which 'fits snugly in the groove 5 of the cell. The diaphragm proper is of woven asbestos cloth 44. The outer edge is preferably blanked off for about three inches radially by a rubber strip 45. The asbestos cloth is prevented from sagging against the face of the anode by any suitable means, but preferably by sewing glass rods (not shown) at convenient intervals onto the face of the cloth on the anode side.

Many variations in mechanical detailsof construction are possible without departing from the spirit of our invention.

Having thus described our invention, what we claim as new and desire to secure by Letters Patent is:

1. In a cell for the electro-deposition of metal, cathode compartments and anode. compartments, porous diaphragms separating said compartments, means for introducing catholyte into the cathode compartment and maintaining same at a constant level, means for removing anolyte from the anode compartments, common channels connected with the anode compartments on each side, and means for automatically admitting catholyte so as to maintain the level of the anolyte substantially constant.

2. In a cell for the electro-deposition of metal, cathode compartments and anode compartments, porous ,diaphragms separating said compartments, means for introducing catholyte into-the cathode compartment and maintaining same at a constant level, means or removing anolyte from the anode compartments, common' channels connected with the anode compartment on each side, means for circulating anolyte from the common channel on one side to that on the other, heating means immersed in the circulating anolyte, and means for automatically admitting catholyte into the common anolyte channels so as to maintain the level of the anolyte substantially contant.

3, In a cell for electro-deposition of metals wherein the cathode and anode compartments are separated by porous diaphragms, means for maintaining a pre-determined level of catholyte in the cathode compart ments, means for withdrawing a constant volume of anolyte from the anode eompart= 1o A ing a pre-determined level of catholyte in porous v diaphra comprising cathode and anode compartments, 1

porous diaphragms separating said compartments, means for introducing catolyte to the cathode compartments, means for maintainsaidcathode comparments, means for withdrawing a constant volume of 'anolyte from the anode compartments, andnieans automatically eflective 7 below a predtermined level to admit catholyte thereto without traversing the porous for electro-deposition of metals, comprising cathode and anode com 'artments, porous .diaphragms separating sai compartments, means for supplying catholyte tothe cathode compartments and maintaining the same therein at a constant level,'means for gms. 5. A cell maintaining a constant circulation of the anolyte, and means for withdrawing anolyte in constant volume, and means automatically eflective when the anolyte falls below a predetermined level for admitting catholyte thereto.

6. A cell for. electro-deposition of metals, comprising cathode and anode com artments, diaphragms separating said compart Inents, disc-like cathodes arranged in the cathode compartments, anodes suspended in the anode compartments, means for supplying 'catholyte to the cathode compartments and maintainin a constant level of catholyte therein, means or withdrawing a portion of the anolyte from one end of theanode compartments and returning the same to the uor inzthe anode compartments.

when the anolyte falls= opposite end, heating means included in' said last-mentioned means, ing a regulatable volume of anolyte from the anode compartments, and means for mainmeans for withdrawtaining a substantially constant level of liqv 7,111 a Cell. of the character described, a porous diaphragm, for separating the cathode and anode compartments, said diaphragm comprising a rubber-covered metal-' lic form comprised of a main peripheral member, and secondary vertical supporting members, a porous diaphragm of asbestos cloth, having vulcanized rubber attaching strips impregnated therein and securely fastenerd to the said metallic'form by joining the said attaching strips to therubber covering of said form.

8. A cell for electro-deposition of metals comprising cathode and anode compartments, porous diaphragms separating said "compartments, disc-like cathodes arranged.

in the cathode compartments, anodes susnded in the anode compartme ts, means dr supplying catholyte-to the cat ode comartments'and maintaining a constant level of catholyte therein, means for circulating the anolytethrough the anode compartments at a substantially, greater rateof flow than the net withdrawal of anolyte from .the cell, heating means for supplying heat to the anolyte .while circulating, means for withdrawing a reg'ulatable volume of anolyte-from the anode compartments, and' means for maintaining a substantially constant level of liquor in the anode compartments, slightly lower than the level of the liquor in the cathode compartments. I

ROBERT D. PIKE. GEORGE H. WEST. BENJALUN PLUMIMER LITTLE. 

